Salt A N, Ohyama K, Thalmann R
Department of Otolaryngology, Washington University School of Medicine, St. Louis, Missouri 63110.
Hear Res. 1991 Nov;56(1-2):37-43. doi: 10.1016/0378-5955(91)90151-x.
Radial communication between ST and SV was measured in the sealed cochlea by monitoring the dispersal of an ionic tracer, trimethylphenylammonium (TMPA) injected in the form of a minute bolus. Tracer movements were recorded by a pair of ion-selective electrodes sealed into the injected and non-injected scalae close to the injection site. Measurements were made in the basal or third turn of the guinea pig cochlea. In the third turn, radial communication occurred rapidly with a ST half time from ST to SV of 25 min and from SV to ST of 26 min. In the basal turn the communication was markedly slower, with a ST half time from ST to SV of 170 min and from SV to ST of 240 min. However, the difference between the basal and third turns can be shown to arise almost totally from differences in cross-sectional area of the perilymphatic scalae. When normalized with respect to scala cross-section, the process of tracer movement across the spiral ligament is similar in the basal and third turns. These results demonstrate that radial communication between scala tympani and scala vestibuli is an important route which must be considered in studies involving perilymph.
通过监测以微小团注形式注入的离子示踪剂三甲基苯基铵（TMPA）的扩散，在密封的耳蜗中测量了鼓阶（ST）和前庭阶（SV）之间的径向连通性。示踪剂的移动通过一对密封在靠近注射部位的注射和未注射的阶中的离子选择性电极进行记录。测量在豚鼠耳蜗的基部或第三转进行。在第三转中，径向连通迅速发生，从鼓阶到前庭阶的鼓阶半衰期为25分钟，从前庭阶到鼓阶的半衰期为26分钟。在基部转中，连通明显较慢，从鼓阶到前庭阶的鼓阶半衰期为170分钟，从前庭阶到鼓阶的半衰期为240分钟。然而，可以证明基部转和第三转之间的差异几乎完全源于外淋巴阶横截面积的差异。当相对于阶的横截面积进行归一化时，示踪剂穿过螺旋韧带的移动过程在基部转和第三转中是相似的。这些结果表明，鼓阶和前庭阶之间的径向连通是一个重要途径，在涉及外淋巴的研究中必须予以考虑。
